XEmacs 21.4.6 "Common Lisp".

[chise/xemacs-chise.git.1] / src / ntheap.c

diff --git a/src/ntheap.c b/src/ntheap.c
index 9372dd1..0f31ff5 100644 (file)
--- a/src/ntheap.c
+++ b/src/ntheap.c
@@ -227,17 +227,44 @@ sbrk (unsigned long increment)
 void
 recreate_heap (char *executable_path)
 {
-  void *tmp;
-
   /* First reserve the upper part of our heap.  (We reserve first
-     because there have been problems in the past where doing the
-     mapping first has loaded DLLs into the VA space of our heap.)  */
-  tmp = VirtualAlloc ((void *) get_heap_end (),
-                     get_reserved_heap_size () - get_committed_heap_size (),
-                     MEM_RESERVE,
-                     PAGE_NOACCESS);
+        because there have been problems in the past where doing the
+        mapping first has loaded DLLs into the VA space of our heap.)  */
+
+  /* Query the region at the end of the committed heap */
+  void *tmp;
+  MEMORY_BASIC_INFORMATION info;
+  DWORD size;
+  unsigned char* base = get_heap_end ();
+  unsigned char* end  = base + get_reserved_heap_size () - get_committed_heap_size ();
+  VirtualQuery (base, &info, sizeof info);
+  if (info.State != MEM_FREE)
+       {
+         /* Oops, something has already reserved or commited it, nothing we can do but exit */
+         char buf[256];
+         wsprintf(buf,
+                          "XEmacs cannot start because the memory region required by the heap is not available.\n"
+                          "(BaseAddress = 0x%lx, AllocationBase = 0x%lx, Size = 0x%lx, State = %s, Type = %s)",
+                          info.BaseAddress, info.AllocationBase, info.RegionSize,
+                          info.State == MEM_COMMIT ? "COMMITED" : "RESERVED",
+                          info.Type == MEM_IMAGE ? "IMAGE" : info.Type == MEM_MAPPED ? "MAPPED" : "PRIVATE");
+         MessageBox(NULL, buf, "XEmacs", MB_OK | MB_ICONSTOP);
+         exit(1);
+       }
+
+  /* Now try and reserve as much as possible */
+  size = min (info.RegionSize, end - base);
+  tmp = VirtualAlloc (base, size, MEM_RESERVE, PAGE_NOACCESS);
   if (!tmp)
-    exit (1);
+       {
+         /* Can't reserve it, nothing we can do but exit */
+         char buf[256];
+         wsprintf(buf,
+                          "XEmacs cannot start because it couldn't reserve space required for the heap.\n"
+                          "(VirtualAlloc at 0x%lx of 0x%lx failed (%d))", base, size, GetLastError());
+         MessageBox(NULL, buf, "XEmacs", MB_OK | MB_ICONSTOP);
+         exit (1);
+       }
 
   /* We read in the data for the .bss section from the executable
      first and map in the heap from the executable second to prevent
@@ -264,13 +291,15 @@ round_heap (unsigned long align)
     sbrk (need_to_alloc);
 }
 
-#if (_MSC_VER >= 1000)
+#if ((_MSC_VER >= 1000) && (_MSC_VER < 1300))
 
 /* MSVC 4.2 invokes these functions from mainCRTStartup to initialize
    a heap via HeapCreate.  They are normally defined by the runtime,
    but we override them here so that the unnecessary HeapCreate call
    is not performed.  */
 
+/* MSVC 7.0 does not allow you to redefine _heap_init or _heap_term. */
+
 int __cdecl
 _heap_init (void)
 {